🇺🇸 Texas Instruments TI 99/4A: Part 3 (PAL Component Video Output) [TCE #0535]
22@JVHShack pointed out in Part 2 [TCE #0534] comments that the PAL machines have a 6-pin DIN socket for video output as they use the TMS9929A VDP that outputs a PAL YUV component signal, rather than the NTSC composite signal that the TMS9918A is limited to.
Yay!
Note that this isn't an RGB output but "component" output, otherwise indicated as Y/Pb/Pr or Y/Cb/Cr (yes, RGB is also component video but I'm referring to what consumer devices expect a component signal to be).
An RGB signal can be generated from these by using a TMS-RGB board, for example.
So let's see if my Aussie 99/4A works. These are pretty rare, IMHO, and I was quite lucky to pick this one up on ebay ... don't see them that often ... again, IMHO.
I might end up putting the TMS-RGB board in and re-wiring the 6-pin DIN video socket to match the Amstrad CPC, albeit with sound on a pin instead of the Amstrad's luminance.
https://tms-rgb.com/
Part 2:
• 🇺🇸 Texas Instruments TI 99/4A: Part 2...
Part 4:
• 🇺🇸 Texas Instruments TI 99/4A: Part 4...
00:00 ... My Aussie PAL machine
03:00 ... TMS-RGB boards to generate RGB from YUV output of the TMS9929A
07:20 ... Almost fully dismantled
08:49 ... TMS9929A information
10:00 ... Testing just B&W (luma) output to see if the machine is working or not
12:34 ... PAL machine's video pinout
13:30 ... Making the YUV video cable
16:45 ... My customised pinout
20:00 ... Finally testing if the cable works
22:25 ... More talk about the TMS-RGB
24:45 ... Component video decoders (Avencore & GBS8200)
25:24 ... Channel outro/thanks
Alternate power supplies (from Part 1 video):
[1] A replacement power supply that generates the DC voltages directly and has the correct plug. You will need to modify the internal power board to bypass itself totally:
hthttps://www.keelog.com/power-supply/#ti99[2] Replace the internal power board with something like this that only requires a regulated 12VDC power supply. You can either replace the power socket with a 2.1mm socket or cannibalise the original plug:
hthttps://github.com/dabonetn/ti99psu-replacement[3] Use a Mean Well GP25A13A-R1B as the power supply and remove the internal PSU board, wiring a 5-pin DIN socket to the internal cabling.
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